The increasing use of mobile computing devices drives the need for improving device power efficiency and responsiveness. The ability of mobile computing device hardware and operating systems to closely manage the power of one or more peripheral devices attached to the host platform independent from other platform components is becoming increasingly important. Said peripheral devices may utilize interconnection standards such as Peripheral Component Interconnect express (PCIe), Serial Advanced Technology Attachment (SATA), Small Computer Systems Interface (SCSI), Fibre Channel (FC), SCSI over Internet (iSCSI), Serial Attached SCSI (SAS), Universal Serial Bus (USB), or any functionally equivalent protocol for peripheral devices.
To enable aggressive power/battery life performance for mobile devices, the SATA interface utilizes the DevSleep interface power state. DevSleep enables host platforms and peripheral devices to completely shut down the SATA interface; this power state results in more power savings compared to other existing Partial and Slumber interface power states, which require that the physical layers (PHY) of the host platform and peripheral device be left powered on.
Descriptions of certain details and implementations follow, including a description of the figures, which may depict some or all of the embodiments described below, as well as discussing other potential embodiments or implementations of the inventive concepts presented herein. An overview of embodiments of the invention is provided below, followed by a more detailed description with reference to the drawings.